High-Density Lipoprotein Cholesterol (HDLC)
| High-Density Lipoprotein Cholesterol (HDLC) | | | |
| Number | | 001925 |
| CPT | | 83718 |
| Related Information | | Lipid Appendix Lipid Panel Lipid Panel With LDL:HDL Ratio Lipid Panel With Total Cholesterol:HDL Ratio |
| Synonyms | | Alpha-Lipoprotein Cholesterol ; HDLC ; HDL Cholesterol ; HDL Cholesterol Electrophoresis |
| Specimen | | Serum |
| Volume | | 1 mL |
| Minimum Volume | | 0.5 mL |
| Container | | Gel-barrier tube or transport tube |
| Collection | | Separate serum from cells within 45 minutes of collection. |
| Storage Instructions | | Maintain specimen at room temperature. |
| Patient Preparation | | Patient should be on a normal diet and maintain a stable weight for a week prior to testing. Any drugs should be discontinued for 3-4 weeks if possible. Test should not be done until 3 months after a myocardial infarction or similar traumatic episodes such as severe infection or inflammation. |
| Causes for Rejection | | Improper labeling |
| Reference Interval | | <40 mg/dL is the cutpoint for increased CHD risk; high HDL cholesterol levels (≥60 mg/dL) decrease CHD risk. See the Lipid Appendix . |
| Use | | A protective substance utilized for prediction of coronary arterial disease, especially useful in individuals with high serum cholesterol levels. Low HDLC is an important predictor of risk of coronary atherosclerosis and coronary heart disease. HDL may act as a protective scavenger molecule (reverse cholesterol transport). The liver is the major site of cholesterol excretion. |
| Methodology | | Enzymatic |
| Additional Information | | Total cholesterol and triglycerides are required as well for determination of lipid risk factors for coronary artery disease. These tests with HDLC and LDLC are the usual lipid panel. HDLC is especially apt to be low in male subjects who are obese and sedentary, in those who smoke cigarettes, and in those who have diabetes mellitus. Uremia is also associated with lower HDLC. Exercise, appropriate diet and moderate ethanol intake increase HDLC. HDLC is useful with cholesterol in forecasting protection against coronary artery disease in the industrialized countries, possible because of ingestion of high fat diets. LDLC, an excellent predictor, is usually a calculation. Those at least risk for development of coronary arterial disease would have low cholesterol, low triglyceride, and high HDLC. Thiazides and nonselective beta-adrenergic blocking agents may decrease HDLC.1 For risk factors including glucose intolerance, increased systolic blood pressure, cigarette smoking, and left ventricular hypertrophy as well as cholesterol, see Figure 1 of paper of Kannel et al.2 Apolipoprotein A-1 determination may eventually be shown to be superior to HDLC; increased apoprotein A-1 is associated with a diminished risk of atherogenesis. It is measured by RIA3 and by nephelometry. Apolipoprotein A-1 is the major protein of HDL. Essentially, current studies have not yet answered whether or not apoprotein A-1 is a better discriminator than HDL.4 At present, HDL measurement is considered preferable by Gordon and Rifkind.5 Factors contributing to decreased HDLC include: - genetic factors: primary hypoalphalipoproteinemia6
- cigarette smoking7
- obesity7
- hypertriglyceridemia7
- lack of exercise
- steroids - androgens, progestogens, anabolic
- thiazides
- beta-adrenergic blockers
- probucol
- neomycin
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| Footnotes | | - Betteridge DJ, “High Density Lipoprotein and Coronary Heart Disease,” BMJ, 1989, 298(6679):974-5.
- Kannel WB, Castelli WP, and Gordon T, “Cholesterol in the Prediction of Atherosclerotic Disease. New Perspectives Based on the Framingham Study,” Ann Intern Med, 1979, 90(1):85-91.
- Maciejko JJ, Holmes DR, Kottke BA, et al, “Apolipoprotein A-1 as a Marker of Angiographically Assessed Coronary-Artery Disease,” N Engl J Med, 1983, 309(7):385-9.
- Miller NE, “Associations of High Density Lipoprotein Subclasses and Apolipoproteins With Ischemic Heart Disease and Coronary Atherosclerosis,” Am Heart J, 1987, 113(2 Pt 2):589-97 (review).
- Gordon DJ and Rifkind BM, “High Density Lipoprotein - The Clinical Implications of Recent Studies,” N Engl J Med, 1989, 321(19):1311-6.
- Grundy SM, Goodman DS, Rifkind BM, et al, “The Place of HDL in Cholesterol Management: A Perspective From the National Cholesterol Education Program,” Arch Intern Med, 1989, 149(3):505-10.
- Frohlich JJ and Pritchard PH, “The Clinical Significance of Serum High Density Lipoproteins,” Clin Biochem, 1989, 22(16):417-23
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